PAT file

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Revision as of 09:05, 4 November 2012 by Razoola (talk | contribs) (→‎Format)
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PAT files contain structured data to patch already loaded Z80 code. They're used to replace sound samples addresses originally loaded from Z80 files when different PCM files are used.

  • Maximum file size: ?
  • Type code: 5
  • Loadable in: Z80 RAM
  • Banks: 1

Format

Blocks of 5, 16bit values:

  • Patch address (in bytes, all the $0000~$FFFF range seems to work)
  • First data word is (/2), byteswapped and written to address
  • Second data word is (/2)-1, byteswapped written to address+2
  • Third (optional) data word is (/2), byteswapped and written to address+4
  • Fourth (optional) data word is (/2)-1, byteswapped written to address+6

If third data word is 0x0000 both the third and forth patches are skipped.